<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        table tr td{
            width: 50px;
            height: 30px;
            text-align: center;
        }
    </style>
</head>
<body>
    <table border="1" style="border-collapse: collapse;">
        <tr>
            <td>1</td>
            <td>2</td>
            <td colspan="2">3</td>
            <!--<td>4</td>-->
            <td>5</td>
        </tr>
        <tr>
            <td colspan="3">6</td>
            <!--<td>7</td>-->
            <!--<td>8</td>-->
            <td>9</td>
            <td rowspan="3">10</td>
        </tr><tr>
            <td>11</td>
            <td rowspan="2">12</td>
            <td>13</td>
            <td>14</td>
            <!--<td>15</td>-->
        </tr><tr>
            <td>16</td>
            <!--<td>17</td>-->
            <td>18</td>
            <td>19</td>
            <!--<td>20</td>-->
        </tr>
    </table>
</body>
</html>